/Engine/Source/Runtime/Core/Public/Misc/DateTime.h
The allow ranges for the components are: Year: 1 - 9999 Month: 1 - 12 Day: 1 - DaysInMonth(Month) Hour: 0 - 23 Minute: 0 - 59 Second: 0 - 59 Millisecond: 0 - 999
true if the components are valid, false otherwise.
static bool Validate ( int32 Year, int32 Month, int32 Day, int32 Hour, int32 Minute, int32 Second, int32 Millisecond )